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1.
Weekly Epidemiological Monitor. 2016; 09 (49): 1
en Inglés | IMEMR | ID: emr-187389

RESUMEN

In the Eastern Mediterranean Region of WHO, seasonal influenza peaked at the end of 2015 and beginning of 2016 and returned to low levels by mid May 2016. In most of the countries, the timing of the season generally corresponded to patterns seen in the previous years


Asunto(s)
Virus de la Influenza A/aislamiento & purificación , Virus de la Influenza B/patogenicidad , Subtipo H1N1 del Virus de la Influenza A , Subtipo H3N2 del Virus de la Influenza A
2.
EMHJ-Eastern Mediterranean Health Journal. 2016; 22 (7): 523-532
en Inglés | IMEMR | ID: emr-181509

RESUMEN

Information on the prevalence of influenza, circulating virus subtypes and seasonality is essential for selecting strains for annual vaccines and for planning immunization programmes. Data were obtained from the 13 sentinel surveillance sites throughout Egypt during 2012-2015. Laboratory-confirmed influenza was found in 13% of cases of influenza-like illness [ILI] and 18% of cases of severe acute respiratory infection [SARI]; positivity for influenza was similar in cases of ILI and SARI in patients up to 15 years of age but increased for SARI and decreased for ILI in people aged >/- 15 years . The most commonly observed influenza virus subtypes were B followed by A/H3 in ILI cases, and A/H1N1 followed by B in SARI cases. The seasonality of influenza in ILI cases was November-February, and that in SARI cases was November-March, peaking in January


Asunto(s)
Humanos , Femenino , Masculino , Recién Nacido , Lactante , Preescolar , Niño , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Infecciones del Sistema Respiratorio/epidemiología , Virus de la Influenza B/patogenicidad , Vacunas contra la Influenza/uso terapéutico , Subtipo H1N1 del Virus de la Influenza A/inmunología
3.
Rev. cuba. med. trop ; 66(2): 273-285, Mayo.-ago. 2014.
Artículo en Español | LILACS, CUMED | ID: lil-731979

RESUMEN

(au)INTRODUCCIÓN: la terapia antiviral frente a las infecciones provocadas por virus influenza se basa en empleo de inhibidores de las proteínas M2 y neuraminidasa (NA). Sin embargo, la emergencia de cepas estacionales resistentes a ambos grupos de fármacos motiva la búsqueda de nuevos fármacos anti-influenza. Los extractos de algas pueden ser utilizados como fuente para la obtención de estos compuestos, teniendo en cuenta la diversidad de metabolitos descrita en estos organismos. OBJETIVO: evaluar la actividad antiviral in vitro de un extracto acuoso del alga roja Laurencia obtusa frente a virus influenza A (H1N1), A (H3N2) e influenza B. MÉTODOS: se evaluó la citotoxicidad en células MDCK, mediante cálculo de la viabilidad celular, en presencia de concentraciones crecientes del extracto. Los efectos sobre la replicación viral se cuantificaron mediante determinación de los niveles de la hemaglutinina (HA) y de la inhibición del efecto citopático (ECP). El índice selectivo (IS) se calculó a partir de la relación IS=CC50/CE 50. RESULTADOS: el extracto acuoso de Laurencia obtusa posee actividad antiviral in vitro frente a virus influenza B, A (H3N2) y A (H1N1) con valores de IS de 7,73; 11,79 y 12,95; respectivamente. CONCLUSIONES: Laurencia obtusa inhibe la replicación de virus influenza de elevada importancia clínica. La realización de ensayos secundarios de caracterización de la actividad biológica, así como de caracterización molecular del extracto, podrían permitir el desarrollo de novedosos compuestos antivirales. Este trabajo constituye el primer informe de actividad inhibitoria de esta especie de macroalga frente a virus influenza.compuestos antivirales. Este trabajo constituye el primer informe de actividad inhibitoria de esta especie de macroalga frente a virus influenza(AU)


INTRODUCTION: antiviral therapy against infections caused by influenza viruses is based on the use of inhibitors of M2 protein and neuraminidase (NA). However, the emergence of seasonal strains resistant to both drug groups has led to the search for new anti-influenza medications. Extracts from algae may be used as a source of compounds, considering the diversity of metabolites described for these organisms. OBJECTIVE: evaluate the in vitro antiviral activity of an aqueous extract from the red alga Laurencia obtusa against influenza A (H1N1), A (H3N2) and B viruses. METHODS: cytotoxicity was evaluated in MDCK cells by cell viability estimation in the presence of growing concentrations of the extract. The effects over viral replication were quantified by determining hemagglutinin (HA) levels and inhibition of the cytopathic effect (CPE). The selective index (SI) was estimated by SI=CC50/CE50. RESULTS: the aqueous extract of Laurencia obtusa showed in vitro antiviral activity against influenza B, A (H3N2) and A (H1N1) viruses with SI values of 7.73, 11.79 and 12.95, respectively. CONCLUSIONS: Laurencia obtusa inhibits the replication of influenza viruses, a fact of great clinical importance. Secondary assays to characterize the biological activity and molecular composition of the extract may lead to the development of novel antiviral compounds. The present paper is the first report on the inhibitory activity of this macroalga species against influenza viruses(AU)


Asunto(s)
Humanos , Masculino , Femenino , Virus de la Influenza A/patogenicidad , Virus de la Influenza B/patogenicidad , Gripe Humana/terapia , Antivirales/uso terapéutico , Extractos Vegetales/farmacología , Laurencia/efectos de los fármacos , Rhodophyta/química
4.
Braz. j. vet. res. anim. sci ; 41(6): 379-383, nov.-dez. 2004. tab, graf
Artículo en Inglés | LILACS | ID: lil-414294

RESUMEN

O objetivo deste estudo foi investigar em cavalos, a incidência do vírus influenza e seu ciclo de transmissão interespécies. Portanto, levantamento sorológico foi realizado em soro de cavalos, confrontados com ambas cepas, as específicas (eqüino) e não específicas (humana) deste vírus. Sangrias de cavalos realizadas nos anos de 1999 e de 2000, forneceram soros que, após tratamento com Caolim (20%) e hemácias de galo(50%) para remoção dos anticorpos inespecíficos, foram titulados contra ambas referidas cepas, através do teste de Inibição da Hemaglutinação (recomendado pela OMS). Os resultados, demonstraram que as respostas sorológicas dos cavalos apresentaram reação cruzada entre as cepas específicas e as não específicas. As porcentagens de títulos IH obtidos foram de 62,75% e de 60,65% para as cepas específicas A/Eq1 (H7N7) e A/Eq2 (H3N8), respectivamente. E às cepas não específicas essas porcentagens foram de: 79,05% para A (H1N1), de 94,45% para A (H3N2) e de 77,75% ao tipo B. O mais relevante nestes dados comparativos com vírus influenza, foi a alta porcentagem de resposta protetora à cepa não específica comparada àquela específica, detectada nos soros eqüinos. Considerando o fato de que o tipo B, deste vírus, ser restrito à espécie humana, portanto a resposta de proteção nos cavalos sugere uma direta transmissão interspécies, como em viroses zoonóticas. Os autores relatam pela primeira vez este tipo de evento no Brasil.


Asunto(s)
Animales , Anticuerpos Antivirales/inmunología , Caballos/inmunología , Caballos/sangre , Virus de la Influenza A , Virus de la Influenza A/patogenicidad , Virus de la Influenza B/patogenicidad , Zoonosis/transmisión , Zoonosis/virología , Reacciones Cruzadas/inmunología , Pruebas de Inhibición de Hemaglutinación/veterinaria
5.
Braz. j. med. biol. res ; 30(12): 1415-20, Dec. 1997. tab, graf
Artículo en Inglés | LILACS | ID: lil-212584

RESUMEN

In the present investigation we studied the fusogenic process developed by influenza A, B and C viruses on cell surfaces and different factors associated with virus and cell membrane structures. The biological activity of purified virus strains was evaluated in hemagglutination, sialidase and fusion assays. Hemolysis by influenza A, B and C viruses ranging from 77.4 to 97.2 percent, from 20.0 to 65.0 percent, from 0.2 to 93.7 percent and from 9.0 to 76.1 percent was observed when human, chicken, rabbit and monkey erythrocytes, respectively, were tested at pH 5.5. At this pH, low hemolysis indexes for influenza A, B and C viruses were observed if horse erythrocytes were used as target cells for the fusion process, which could be explained by an inefficient receptor binding activity of influenza on N-glycolyl sialic acids. Differences in hemaglutinin receptor binding activity due to its specificity to N-acetyl or N-glycolyl cell surface oligosaccharides, density of these cellular receptors and level of negative charges on the cell surface may possibly explain these results, showing influence on the sialidase activity and the fusogenic process. Comparative analysis showed a lack of dependence between the sialidase and fusion activities developed by influenza B viruses. Influenza A viruses at low sialidase titers (<2) also exhibited clearly low hemolysis at pH 5.5 (15.8 percent), while influenza B viruses with similarly low sialidase titers showed highly variable hemolysis indexes (0.2 to 78.0 percent). These results support the idea that different virus and cell-associated factors such as those presented above have a significant effect on the multifactorial fusion process.


Asunto(s)
Conejos , Animales , Virus de la Influenza A/patogenicidad , Virus de la Influenza B/patogenicidad , Gammainfluenzavirus/patogenicidad , Fusión de Membrana/inmunología , Glicoproteínas de Membrana , Virus de la Parainfluenza 1 Humana/patogenicidad , Proteínas Virales de Fusión , Pollos , Membrana Eritrocítica , Haplorrinos , Caballos , Gripe Humana/fisiopatología , Ácido N-Acetilneuramínico , Neuraminidasa , Ácidos Siálicos
6.
Acta méd. colomb ; 17(1): 63-7, ene.-feb. 1992. ilus, tab
Artículo en Español | LILACS | ID: lil-183212

RESUMEN

Se describe el caso de una mujer joven atendida en el hospital San Ignacio (Santa Fe de Bogotá), con diagnostico post mortem de síndrome de Reye. Seguidamente, se revisan y discuten los aspectos fisiopatológicos y los concernientes al diagnóstico y la terapéutica.


Asunto(s)
Humanos , Femenino , Adulto , Virus de la Influenza B/patogenicidad , Síndrome de Reye/complicaciones , Síndrome de Reye/diagnóstico , Síndrome de Reye/epidemiología , Síndrome de Reye/etiología , Síndrome de Reye/fisiopatología , Síndrome de Reye/mortalidad , Síndrome de Reye/patología , Síndrome de Reye/tratamiento farmacológico , Síndrome de Reye/terapia
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